Total number of moles of `EDTA^(4-)` required to produce octahedral complex with `Mg^(2+)` is

Explanation

To determine the total number of moles of `EDTA^(4-)` required to produce an octahedral complex with `Mg^(2+)`, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Coordination Complex**:
- An octahedral complex is formed when a central metal ion is surrounded by six ligands. This is characterized by a coordination number of 6.

2. **Identifying the Metal Ion and Ligand**:
- In this case, the metal ion is `Mg^(2+)` and the ligand is `EDTA^(4-)`.

3. **Recognizing the Nature of EDTA**:
- `EDTA` (Ethylenediaminetetraacetic acid) is a hexadentate ligand, meaning it can form six bonds with a metal ion.

4. **Formation of the Complex**:
- When `Mg^(2+)` interacts with `EDTA^(4-)`, it forms a complex represented as `Mg(EDTA)^(2-)`. This indicates that one `EDTA` molecule coordinates with one `Mg` ion.

5. **Calculating the Number of Moles**:
- Since one `EDTA^(4-)` ligand can bind to one `Mg^(2+)` ion to form the octahedral complex, only one mole of `EDTA^(4-)` is required for each mole of `Mg^(2+)`.

### Final Answer:
The total number of moles of `EDTA^(4-)` required to produce an octahedral complex with `Mg^(2+)` is **1 mole**.

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